Pad used on crutches, artificial limbs, and sticks



F. C. LYNDE. PAD USED ON CRUTCHES, ARTIFICIAL LIMBS AND STIOKS-..

Patented May 18, 1920.

APPLICATION FILED S'EPT- 27,1918- 2 y wzvze g FREDERICK CHARLES LYNDE,

OF MANCHESTER, ENGLAND.

PAD USED ON GRUTCHES, ARTIFICIAL LIMBS, AND STICKS.

Specification of Letters Patent.

Patented May 18, 1920.

' Application filed September 27, 1918. Serial No. 255,950.

To all whom it may concern Be it known that I, Fnnnnnrox CHARL-ns LYNDE, a British subject, residing at Manchester, in the county of Lancaster, England, have invented certain new and useful Improvements in Pads Used on Crutches, Artificial Limbs, and Sticks; and I do hereby declare that the following isa full, clear, and exact descriptionof the same.

This invention relates to elastic or resilient pads or buffers for the end of crutches,

artificial limbs and sticks which are used to subdue the shock or concussion on str king the ground, in which a removable resilient block is secured in a socket of rubber or metal fitted on to the end, the resilient block being usually made of solid rubber.

This invention is designed to prevent slipping, to increase the resilience givlng greater ease to the user, and to conform more readily to the contour of the ground by adjusting the bottom surface thereto automatically, while at the same time providing for the renewal of the wearing part.

The invention comprises a pad formed as a double socket the upper part to fit on to the crutch or stick, and the lower part to receive a removable or renewable block, and consists in forming a recess or air cavity n the removable block or in the socket 0r 1n both to provide a pneumatic cushion which will enable the bottom surface to conform more readily to the contour of the ground and give greater resilience thereto w th which may also be incorporated a non-slipping material.

The invention will be fully described with reference to the accompanying drawings which show several examples of the invention.

Figure 1 is a sectional elevation of one form of the invention.

Fig. 2 is a transverse section of same.

Fig. 3 is a plan from below.

Figs. 4:, 5 and 6 are sectional elevations showing other forms of the invention.

The pad or buffer is constructed with an upper portion A formed with a socket a to fit on to the end of the crutch or stick in the ordinary way and an undercut-or dovetail socket (1 below the end of'the crutch and with a resilient block B removable an renewable to fit into the lower socket a.

The upper portion A may be of rubber, metal or other material molded, cast or stamped or otherwise made to the desired shape, and the lower portion or block B may be made of rubber, rubber composition, leather, vulcanized fiber or paper, rubber or leather substitute, or other suitable material, and with any of these compositions or combination of any of them'may be incorporated with or without liquid india-rubber cement a non-slipping material such as layers, coils, tubes or rings of canvas or insertion rubber hose, webbing, asbestos fibers or fabric, silicate cotton, hair, shredded metal compressed or otherwise, wire compressed or otherwise, woven wire placed on edge or otherwise, carborundum, emery, quartz, or granite.

The removable resilient block B is also made with a recess or cavity 6 which .forms a pneumatic cushion and increases the resilience thereof.

The upper part A may when made of rubber be bound around with a metal ring C to retain the lower portion B in position and the lower portion B may be bound with a metal ring 0 to prevent spreading at the bottom, and by compression of the ring to consolidate the material forming the bottom surface and thus cause the pad to wear a longer time.

In the example shown in Figs. 1, 2 and 3 the upper portion A of the pad is made of rubber or of metal such as aluminium with a socket a for the end of the crutch and a socket a shaped or molded to receive the end of the block B of rubber or other resilient material into which is incorporated an annular coil or tube 7) of non-slipping material. The block B is made with a cavity 6 which forms a pneumatic cushion and increases the resiliency of the block or under portion B of the pad. A metal ring a may be placed around the lower edge of the block B to prevent spreading and retard wear, the ring 0 gradually moving up the block as it wears. When the block B has worn down to the edge of the socket a it may be removed and replaced. The block B may be made wholly of rubber or other resilient material without the ring of non-slipping material I).

In the example shown in Fig. 4, the construction is similar to that shown in Figs. 1 to 3, with the addition of a plug cl preferably tapering inserted into the mouth of the pneumatic cavity 2) in the block B to force the upper edges outward to tighten and retain the block in position in the socket a. In this case also the block may be made without the non-slipping material 6.

In the example shown in Fig. 5, the upper portion A of the pad is made of rub beror it may be of metal-with a socket a for the end of the crutch or stick and a socket a shaped or molded to receive the end of a block B of rubber. The block B is formed with a cavity 6 which forms a pneumatic cushion and increases the resiliency of the block and permits it more readily to conform to the contour of the ground and increases its resiliency. A metal ring C may be screwed on or other 'wise applied to the exterior of the socket a so as to retain the block B in position. An annular coil of non-slipping material similar to Z) in the previoiis figures may be incorporated in the block B as previously described with a metal ring to compress it, prevent spreading and retard wear. When the block B has worn down to the edge of the socket a it may be removed and replaced.

In the example shown in Fig. 6, the upper portion A of the pad is made of rubber and is similar to that described in Fig. 5, with the addition of an air cavity 0'" to form it into a pneumatic cushion. In this case the lower portion or block B may be either as shown or it may be in the form shown or described with reference to any of the other Figs. 1, a or 5.

The resilient block B may be indented or formed with a slit or slits to any desired extent on the top to increase its resilience and to facilitate insertion into the undercut socket a. i

In the examples shown the bottom surface of the block B is square or at right angles to the vertical axis of the pad. If desired, for any particular construction of crutch, the bottom surface of the block B may be curved or inclined to the vertical axis or so shaped as to accommodate the pad to the angle at which the crutch or stick approaches the ground, thereby approaching the normal shape that it would assume after being worn.

\Vhat I claim as my invention and desire to protect by Letters Patent is 1. A buffer or pad of the character described, comprising a double socket, a resilient block having. an annular insert of non-slipping material incorporated therein and provided with an 'air cavity adapted to form a pneumatic cushion, the sockets and said resilient block being so formed and related that when the pad is placed in position on the member with which it is to be used the cavity is hermetically sealed.

2. A buffer or pad of the character described, comprising a double socket, a re silient block provided with an air cavity to form a pneumatic cushion, an annular insert of non-slipping material incorporated in said resilient block, and a plug member actuated from the upper socket to close said air cavity and to maintain said resilient member in position in the lower socket.

3. A buffer or pad of the character described, comprising a double socket, a resilient blockprovided with an air cavity to form a pneumatic cushion, an annular insert of non slipping material incorporated in said resilient block, and a block sealing and retaining member comprising a head portion adapted to engage the lower portion of the upper socket, and a plug member projecting from said head portion and adapted to close the air cavity in said resilient block.

t. A butter or pad of the character described, comprising a double socket, a resilient block provided with an air cavity to form a pneumatic cushion, an annula'rinsert of non-slipping material incorporated in said resilient block, a block sealing and retaining member comprising a head portion adapted to engage the lower portion of the upper socket, a plug member projecting from said head portion and adapted to close the air cavity in said resilient block, and a metal ring positioned around said resilient member and below the socket members, substantially as described.

Signed atv Manchester, in the county of Lancaster, England, this fourth day of Qleptember 1918.

FREDERICK CHARLES LYNDE.

Witnesses i J. OwonN OBRIEN, J. (irniinvns OBRIEN. 

